METHOD FOR EVALUATING AN ENGINE STARTING SYSTEM

• US 20150361941A1
• Filed: 06/14/2014
• Published: 12/17/2015
• Est. Priority Date: 06/14/2014
• Status: Active Grant

• Current Assignee: GM Global Technology Operations LLC (General Motors Company)
• Original Assignee: GM Global Technology Operations LLC (General Motors Company)
• Inventors: DU, XINYU, NAGOSE, ATUL, ZHANG, YILU
• Granted Patent: US 9,404,466 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: F02N 11/108 for diagnosis of the starter or its components
• CPC Class Codes: F02N 2200/045 Starter temperature or parameters related to it
• CPC Class Codes: G01K 13/00 Thermometers specially adapted for specific purposes
• CPC Class Codes: G01K 2205/00 Application of thermometers in motors, e.g. of a vehicle
• CPC Class Codes: G01M 15/042 by monitoring a single specific parameter not covered by groups G01M15/06 - G01M15/12
• CPC Class Codes: G01M 15/048 by monitoring temperature
• CPC Class Codes: G01R 31/3647 for determining the ability of a battery to perform a critical function, e.g. cranking
• CPC Class Codes: G01R 31/382 Arrangements for monitoring battery or accumulator variables, e.g. SoC

Abstract

An internal combustion engine employs a starting system. A method for evaluating the starting system includes determining a cranking resistance ratio between a starter and a battery of the starting system during engine cranking. The cranking resistance ratio is normalized based upon an operating temperature of the starting system, and the starting system is evaluated based upon the normalized cranking resistance ratio.

Claims

1. A method for evaluating a starting system for an internal combustion engine, comprising:

determining a cranking resistance ratio between a starter and a battery of the starting system during engine cranking;

normalizing the cranking resistance ratio based upon an operating temperature of the starting system; and

evaluating the starting system based upon the normalized cranking resistance ratio.

2. The method of claim 1, wherein the cranking resistance ratio between the starter and the battery is determined based upon an equivalent circuit analytic model of the starting system.

3. The method of claim 2, wherein the equivalent circuit analytic model of the starting system takes the form of the following relationship:

4. The method of claim 3 wherein V_min is determined by capturing a single cranking voltage data point during the engine cranking.

5. The method of claim 1, wherein the cranking resistance ratio is normalized in accordance with the following relationship:

6. The method of claim 5, wherein the starter temperature T_s is determined based upon the battery temperature T_b.

7. The method of claim 6, wherein the starter temperature T_s is determined in accordance with the following relationship:

8. A method for evaluating a starting system for an internal combustion engine, comprising:

determining a cranking resistance ratio between a starter and a battery of the starting system based upon a single datapoint comprising a minimum cranking voltage captured during engine cranking;

normalizing the cranking resistance ratio based upon an operating temperature of the starting system; and

evaluating the starting system based upon the normalized cranking resistance ratio.

9. The method of claim 8, wherein the cranking resistance ratio between the starter and the battery based is determined in accordance with the following relationship:

10. The method of claim 8, wherein the cranking resistance ratio is normalized in accordance with the following relationship:

11. The method of claim 10, wherein the starter temperature T_s based upon the battery temperature T_b.

12. The method of claim 11, wherein the starter temperature T_s is determined in accordance with the following relationship:

13. A method for monitoring an electrical starting system for an internal combustion engine, comprising detecting a fault with one of a starter motor and a battery when a cranking resistance ratio determined between a cranking voltage and an open circuit voltage of the battery is greater than a predetermine threshold, said cranking resistance ratio normalized based upon a temperature of the battery.

14. The method of claim 13, wherein the cranking resistance ratio between the cranking voltage and the open circuit voltage of the battery is determined in accordance with the following relationship:

15. The method of claim 13, wherein the cranking resistance ratio is normalized in accordance with the following relationship:

16. The method of claim 15, wherein the starter temperature T_s is based upon the battery temperature T_b.

17. The method of claim 16, wherein the starter temperature T_s is determined in accordance with the following relationship: